Keyboard clutch



Jan. 15, 1935. w LAWRENCE 1,987,742

" I KEYBOARD CLUTCH Filed Oct. 25, 1931 2 Sheets-Sheet l INVENTQR $0 .M flow/11:786.

ATTORNEY Jan. 15, 1935. G. w. LAWRENCE 1,987,742

KEYBOARD CLUTCH Fil'ed Oct. 23, 1931 2 Sheets-Sheet 2 BY 020 mama fl w v Arronuav Patented Jan. 15, 1935 1,987,742

UNITED-STATES PATENT OFFICE KEYBOARD CLUTCH George W. Lawrence, Los Angelou, Calif assignor to William J. Pearson, Los Angeles, Calif.

Application October 23, 1931, Serial No. 570,623 3 Claims. (Ol. 192--28) This invention relates to a keyboard clutch my claims, and illustrated by the accompanying mechanism designed to be used in conjunction drawings, in which: with a parcel post machine, such as is disclosed Fig. 1 is a front elevatlonal view of an autoin the co-pending application Serial Number matic' keyboard, partly in section.

6 367,106, iiled May 29, 1929, by William J. Fig. 2 is a sectional view in elevation from 6 Pearson, and entitled Parcel post -weighing and the right of the keyboard, showing one clutch stamp printing machine, which is designed to in disengaged position. weight parcel post packages and to print parcel Fig. 3 is a detail of the mechanism shown in post stamps of the prepaid metered type. Fig. 2, showing the clutch engaged and the trip The Parcel post weighing and stamp printing disengaged by depression of a key. 10 machine just referred to is designed for the print- Fig. 4 is a detail similar to Fig. 3, showing the ing of metered parcel post stamps, and, gendriving element and the clutch after having made erally speaking, comprises weighing mechanism, one-half of a revolution, with the key. returned printing mechanism, registering mechanism, and and the trip positioned to release the clutch.

means for setting up on the printing mechanism Fig. 5 is a view similar to Fig. 4, but taken 15 the mechanical equivalent of a number or set of from the opposite side of the device. numbers set up by actuation of the keys of the Fig. 1 illustrates a keyboard designed to be keyboard, used in a parcel post machine wherein a plu- An object of my invention is to provide a keyrality of keys operate a corresponding number board of the simplest form and character to proof clutches to engage and transmit power from 20 vide ease and simplicity of operation for an opa power source (not shown) to do work required erator of an otherwise complicated machine, and in the machine. There is a supporting base 10, to provide a mechanism that will respond to a which may be part of the parcel post machine, very light tough upon the keys of the keyboard; upon which the keyboard unit is mounted by v to that end, I have provided a series of power means of the frame 11; the frame includes ,an up- 25 driven clutches disposed between the keys and per plate 12 iugh which pass the keys 13 and a the machine actuating elements; so that each control key 14 which operates the power clutch key is in effect a clutch actuating element con- (not shown); a portion of the casing 15 for entrolling the connecting of power to the machine closing the machine is shown in Fig. 2.

80 eperating elements. For the purpose of description, the clutches An object. of my invention is to provide a w ll be treated in the singular, and the descripclutch connection between the keys and the tion will read as describin o clutch and its power driven elements which is simple in conc mp t parts only. struction, durable, instantly operable at the touch The drive Shaft 16, which 15 here related by oi a kc and ca able of transmittin the required means of gears and 18 t a source of power 35 y p g i (not shown), rotates continuously and has keyed amount of power to perform the we clutch construction is particularly designed for g fi g i g g pggag g 3 3223 f tgga; use in a machine such as the parcel post weighan engaging element whereby the clutch may be ing and stamp printing machine referred to, instantly contacted for the purpose of transmit- 40 wherein one revolution of the driving element ting power with the least amount! lost time actuates the connected mechanisms the required or motion amount; and wherein there is a power return Upon depression of one of the keys 13, the key the keys after their depression and before the bar 20 moves from the original position Shown 5 completion of the rotation of the clutch, thus pre in Fig. 2 to the position shown in Fig. 3, the senting the clutch releasing element in the path trip lever 1 is rocked on t haft 22 on which of the clutch for the clutch releasing operation, t is mounted and thereby raises t and of t returning e keys to or a p si io and prolever constituting the trip 23; this allows the viding for only one clutch operation from one latch 24, under tension of spring 25, to rock depression of a key. in one direction. Latch 24 is rockably mounted 50 To the above and other objects as may hereon pin 26 in cam 28. The rocking of the latch inafter appear, my invention consists in the 24 by spring 25 brings the tooth 27 into the path novel construction, arrangement, and combine. of one of the teeth on the ratchet wheel 19, tion of parts as hereinafter fully, clearly, and which constitutes the operation of engaging the concisely described and definitely pointed out in clutch. The cam member 28 is rotatably mount- 55 ed on shaft 16, and bears on one side the pin 26 and the stop pin 29, which engages the latch 24 by means of the elongated opening 30. The

latch 24 also has secured to it one end of the 6 spring 25. On its other side cam 28 is provided with an eccentric 32. This eccentric carries and operates an eccentric ring 31, which is provided with an extension 33 connected to a rocking lever 34 by means of a pin 35 on the latter fitted within an elongated opening 36 in the extension; the

rocking bar 34 is mounted by means of a pin 37 in an adjustable bifurcated support 38 on a frame 39 secured to the base 10 by locking nuts 40.

This rocking bar 34 is the means by which movement is transmitted from the clutch to the operative parts of the parcel post machine (not shown).

To return trip lever 21 and key 13 to normal position and coincidently to return the trip 23 into the path of the contact point 41 on the latch 24, so that it may disconnect the clutch at a positive predetermined point in its revolution, I have provided means comprising a shaft 42 running the full length of all of the keys 13 so that all of the keys may be operated upon at the time that any one key has been depressed and the clutch operated. This shaft 42 is mounted in a --series of bell crank levers 43, one being provided for each of the clutches, and all rockably mounted upon a shaft 44 mounted at both ends in the frame 11.

The opposite arm of the bell crank lever 43 is provided with a continuous shaft 45 which is engaged by the bifurcated end 46 of a rocking 36 lever 47 rockably mounted on a shaft 48 to actuate simultaneously all of the bell crank levers 43 and thereby the trips 21. The rocking lever 47 is provided with an extension at its lower end constituting a cam slide 49, which rides upon a peripheral cam face 50 upon the cam 28.

The rotation of the cam member 28 operates to raise the cam slide 49, thereby moving the parts connected to it. This variation in position is best illustrated by the comparison of Figs. 2,

3, and 4, wherein Fig. 4 shows the cam 28 rotated approximately one-half of its rotaltion, thereby forcing cam slide 49 to ride upon the outer peripheral face 50 of the cam; in this position it has actuated the bell crank 43 to the limit so of its movement,'whereby the shaft 42 has contacted the trip lever 21, raising the end of the trip connected to the key bars 20, thus raising the keys and lowering the trip 23 into position to contact the contact point 41 of the latch 24,

66 thereby removing the tooth'2'7 out of contact with the ratchet wheel 19; thus the clutch is disconnected and the several rotatable members comprising the driven section of the'clutch are stopped in their movement at a predetermined point.

The complete rotation of the cam member 28 brings that part of the peripheral face of the cam containing the dwell opposite the cam slide 49, thus allowing it to return into the dwell, and

05 thereby removing the shaft 42 from contact with the trip lever 21 (see Fig. 2) and allowing room for the necessary movement of the trip lever 21 upon actuation of a key before the trip lever 21 will contact the shaft 42.

70 The trip lever 21 is tensioned by a spring 51 secured to a part of a keyboard plate 52, thereby retaining the trip lever 21 in engaged position with the latch 24 after the removal of the shaft 42. The cam slide 49 is tensioned against the face of the cam .28 by means of a spring 53,

In the operation 'of the keyboard clutch one of the keys 13, which constitutes a clutch trip lever, is depressed, and, by means of the connected trip lever 21, the trip 23 is removed from the contact point 41, thereby allowing latch 24, un- 5 der tension of the spring 25, to engage its tooth 27 with one of the teeth of the ratchet wheel 19; the clutch being thus engaged instantly picks up the other members constituting the driven parts of the clutch and rotates them one com- 10 plete revolution; within the interval of time occupied by the rotation of the shaft-16 one revolution, the cam 28 has, by means of the cam slide 49 and its connected parts, returned the trip 23 into the'path of the contact point 41 and the re- 15 suiting engagement of trip 23 with latch 24 has, upon the completion of one revolution of the shaft 16, removed the tooth 27 from contact with one of the teeth of the ratchet wheel 19, thereby removing the driven elements of the clutch from 20 contact with the drive element (shaft 16 and its attached ratchet wheel 19). The one revolution of the cam member 28, which is the main driven member of the clutch, has effected one revolution of the eccentric 32, thereby driving the 26 cam ring 31 and its extension 33 to operate rocking lever 34, thereby transmitting rotary movement from the drive shaft 16 to vertical reciprocating movement of the rocking lever 34.

This form of clutch provides a simple and ef- 30 ficient means for operating an automatic keyboard wherein it is only required that an operator lightly depress one of the keys sufliciently to release the trip 23 from the contacting point 41; the power drive shaft 16 thereupon assumes the 36 load of the operation of the various parts of the parcel post machine which may be actuated by means of the rocking lever 34. The speed of the drive shaft 16 and. therefore, the speed of the movement of the rocking lever 34, may be varied 40 according to the operations to be performed within the parcel post machine by the lever 34. I have provided by means of this clutch a simple and emcient method of transmitting power with a minimum of friction and complication, and with the 46 most ethcient operation in the smallest interval of time. i

The structure of the clutch itself and the means for controlling and actuating the movement thereof, together with the other objects set forth. 50 may be varied in form without departing from my invention as herewith claimed, the showing of this description and drawing being merely an illustration of one embodiment of my invention.

While the form of mechanism here shown and described is admirably adapted to fulfill the objects primarily stated, it is to be understood that it is not intended to confine the invention to the one form of embodiment herein disclosed, for it is m susceptible of embodiment in various forms, all coming within the scope of the claims which follow.

- I claim: I

1. A clutch device comprising a cam, a latch 66 pivotaliy mounted on said cam, a ratchet wheel, a trip member normally engaging said latch to hold said latch out of engagement with said ratchet wheel, means for releasing said trip member to permit engagement of said latch with 70 said ratchet vwheel to cause movement of said cam, and restoring means engaged by said cam and movable by rotation of said cam into engagement with said trip member to move said trip member into the path of rotation of said 76 latch to engage said latch and release said latch from said ratchet wheel,

2. A clutch device comprising a driving member, a drivencam member, a latch pivotally carried by said cam on one side thereof and normally tending to engage said driving member to cause rotation of said cam member therewith, a trip member positioned on the same side of said cam and normally directly engaging and holding said latch out of engagement with said driving member, means for releasing said trip member and clutch-disengaging means comprising a movable member in engagement with said cam and a member operatively connected thereto and adapted to engage-said trip member and project said trip member into position to engage said latch during rotation of said cam to release said latch from engagement with said driving member.

3. In a device of the character described, a

drive shaft, a ratchet wheelfixed to saidshatt,

a cam wheel loosely mounted on said shaft and having a cam face, a latch pivotally secured on one side of said cam wheel, a trip member posi-- tioned on the same side of said cam, said latch havinga tooth adapted to engage said ratchet wheel and a projection directly engageable by said trip member, said trip member normally engaging said projection to hold said latch tooth out of enagement with saidratchet wheel, means for releasing said trip member from said projec-' tion, and restoring means adapted to engage said trip member, said restoring means enga in the cam face of said cam wheel and actuated thereby, said restoring means, during rotation of said cam wheel through engagement of said latch tooth and said ratchet wheel, engaging said trip member and projecting said trip member into position to engage said latch projection to release said latch tooth from said ratchet wheel.

' GEORGE W. 

